Well as luck would have it my issue was not just the battery. A second test a few days later found the bike only charging to 13.08 volts. RR checked out fine again as did the stator. Cleaned all connections but still 13.08 volts. It was enough to ride to work and back a few times with a new battery but ordered the stator and RR anyway.

Pulled the cover off the side and what do you know, a burned pole on the stator. Goes to show I guess numbers can lie when dealing with an intermittent electrical issue. I'll know how the stator works tomorrow when the 1211 silicone gasket has a chance to set up and I can run the bike. Fingers crossed.

This will reduce the load on the alternator, as the OEM basically is running the alternator at maximum output all the time. Second thing I would do if time permitted is take a new stator to a reputable motor shop and have them give it a epoxy dip and bake. One of the leading failures , if you look through many of the photos is, one or two poles failing, this is due to internal turn to turn shorts within the single pole, or shorts turn to ground of the pole piece ( most stators have a epoxy coating over the lamination's, this is very thin, a matter of some vibration and next thing is a grounded winding). This is caused by the magnet wire vibrating and eventually wearing through the insulation, which is typically .003 ", the epoxy dipping is to keep this winding as one solid mass, and prevent the vibration/ wearing through of the insulation . One drawback to too heavy a coating is the reduced cooling , as there will be less oil circulation of the winding.

Thanks Wizard. My company manufacture power tools, so coil winding, bonding, etc is not alien to me. I was thinking of having this service available or teach others to rewind their own, Trickiest part will be the bonding where epoxy is concerned. There are two ways, Powder coating or plain resin trickling. Both requires pre-heat (which some DIYers didn't consider), resin/powder application and heating again. Don't forget to insulate the stack with paper laminates too.

As you can see from the guy with the HONDA, his case was a failure waiting to happen due to the inherent design of the stator and mount. I hope the V has more FMEA in this area. My Compufire is now on backorder 2-3 weeks away.

Thanks Wizard. My company manufacture power tools, so coil winding, bonding, etc is not alien to me. .

Well it has been about 30 years since I worked in a motor shop, at that time they had two types of varnish that we would dip the wound stators or armatures in , then bake in a oven for six to 8 hours. At that time they had a LIQUID epoxy varnish made specifically for motor winding, it cured using heat, they used a class H insulated magnet wire, so the oven temperature was set for around 125'C.

""Don't forget to insulate the stack with paper laminates too.""

Again, 30 years ago they used a product called dmd ( dacron mylar dacron) also used nomex which is used in many present day slot insulations------HOWEVER you will notice the laminations of factory made alternators use a epoxy type coating instead, this is why some people experience stator failure after dropping the bike. The stator expands and contracts and eventually it is possible to chip away if when machine wound there was a thin coating on the edges. Machine winding requires a certain amount of tension / drag on the magnet wire, the edges/ corners of the laminations are prone to magnet wire damage from this tension. If you look closely, (and I have discussed this in previous threads) Electrical system problems. Where do I begin? ---------------read posts 16, 18, 19

Two thoughts. Can an oem stator have a wiring mod to change the unit to an RR type?
Do you think that with the oem stator running full output all the time would cause the insulation on the copper wires in the coils to overheat and break down causing shorted windings and then failure?
I haven't studied/researched as to how both stators are wound.
Just some thoughts.

Because the rotor is a permanent magnet, it operates at full field all of the time. The regulator dumps excess current to ground. Usually, the stators are designed to be operated this way continuously. Obviously, they didn't quite do that with these.

The BMW K bikes actually had a conventional Bosch alternator with a wound rotor, and regulated it by varying the field excitation voltage.

Because the rotor is a permanent magnet, it operates at full field all of the time. The regulator dumps excess current to ground. Usually, the stators are designed to be operated this way continuously. Obviously, they didn't quite do that with these.

The BMW K bikes actually had a conventional Bosch alternator with a wound rotor, and regulated it by varying the field excitation voltage.

Well said, and since we have no control of the field strength, idle RPM will have a lower output than a conventional alternator that has external regulation of the rotor magnetic field.

Last week my stator failed at under 18000 miles and over 600 miles from home, on day three of a long planned week long vacation. However, as luck would have it, I was not alone. I was riding with three friends and we had lots of tools. Finding a new replacement, at a dealer, was always next week. Then we got a line on a bike junkyard, checked what they had but no luck, but while going to the junkyard we passed a powersports outlet so on the way back we stopped. They only sell Chinese made side by sides, but they do have a few stators we can look at. We picked one that looked like it could fit if modified but not plug in. A stop at Advance Auto yielded a soldering gun and heat shrink. We grafted the wiring harness and cut off a large metal wire support. Installed it and got 14.6 volts at 4000 rpm, trip saved..... Rode over three hundred miles just fine but the output under load at night was dismal. Blowing the horn with high beam on dims the lights, but it worked.

So the stator was from a Chinese side-by-side with a Yamaha 660 single engine knockoff?

Not sure which one it was off of, They had four of them and the one we took wasn't the largest. We simply chose the one dimensionally the same and three phase. We later found that the one we took was wound wye and not delta like our original is. Each lead leaving the oem stator terminates to two conductors at the windings the Chinese only one, I figure its maybe 60% capacity at best but it did get the job done. I am going to keep it as a emergency spare, I know it will get me going again if needed.
If I come across the receipt I will post a part number if there is one, I think it just said stator and cash sale.

Well it looks like the receipt is MIA, waiting for the brown truck with the new parts, still running the stator till then.

Went for a ride today, monitoring my LED "voltage monitor" fairly closely. It started out green, then flickered OFF (NO light of any color!) then ON a few times, then the "OFF" cycle became more predominant.

Then it would start being yellow (11.8 to 11.5v), and occasionally red (11.2 >), but still going OFF now and then, and sometimes flickering green (13.2v), so I turned back, heading home, hoping I'd be able to get home w/out pushing. Total ride was 130 kms, 80 miles. (I removed the 10A fuse for the headlight before the ride to give me a bit more volts for the FI, in the event I needed the 'room'.)

The last mile to home the light stayed green, so as soon as I got into the garage, I shut the bike down and got my VOM to check the battery. It came up 13.31v (which is where it SHOULD be!), and now after about an hour it's 13.03v which seems to indicate that it was fully charged.

I ordered the Compufire R/R and I'm going to order a stator, and put them in once I get them.

Any thoughts from you electrical experts?

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I checked the alternator output, and the regulator, and everything checks OK. So I went for an hour and a half ride yesterday, monitoring the LED - and it stayed green.

When this happened I had just washed the bike. I wonder....

"....

Yesterday I 'aborted' a ride to meet up w/ guys I used to fly w/, on their annual ride, and when I got home, after checking the volts (13.3 or so), I put the VOM into a saddlebag and then later I went to meet them about 25 miles north of here in Vernon.

My indicator was putting on a REAL light-show, but STILL 13 v when I got to their hotel, and still at 13v when I got home later. Had to go down town today to get some "stuff", so I checked the voltage MANY times - ALWAYS in the 12.8 to 13.3v range, so I'm now of the opinion that my LED voltage indicator is NOT waterproof, and that when I washed the bike I trashed it. I'm ordering another indicator, but THIS one will be waterproof for sure!

I've already ordered the Compufire R/R and new stator, so I'll put the R/R in, check how the stator looks, and keep it for "whenever" if mine isn't cooked yet.

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I installed a new stator from Ricks, and a new series r/r from Roadstercycle.
I connected the r/r stator pigtail to the wires that went to the old r/r plug, and ran the r/r output wires direct to the battery so the lighting tap is still in the stator circuit. The brown wire from the ignition that went to the old r/r is not connected, when running voltage output is steady at 14.2 volts as it should be and everything is working the same except the headlight, now the headlight is on when you turn on the key. I feel the brown wire is the culprit but has anyone else experienced this?

The problem is not the brown wire..if I remove the fuse in the wiring between the r/r and the battery, the problem goes away. I will add a relay triggered off the headlight and all should be good.

I installed a new stator from Ricks, and a new series r/r from Roadstercycle.
I connected the r/r stator pigtail to the wires that went to the old r/r plug, and ran the r/r output wires direct to the battery so the lighting tap is still in the stator circuit. The brown wire from the ignition that went to the old r/r is not connected, when running voltage output is steady at 14.2 volts as it should be and everything is working the same except the headlight, now the headlight is on when you turn on the key. I feel the brown wire is the culprit but has anyone else experienced this?

The problem is not the brown wire..if I remove the fuse in the wiring between the r/r and the battery, the problem goes away. I will add a relay triggered off the headlight and all should be good.

If you have a meter that measures DC amps, disconnect the battery and insert your meter in series, see if you have any discharge current with everything off. Second it isn't clear where you connected the stator wires, is it the socket by the TPS ? Good chance your headlight relay is turned on through feedback from the new regulator. I have looked at the drawing, if it is what I think, your ECU relay is energizing the headlight relay when you key on because you already have 12VDC positive at the stator AC input to the headlight relay. Second simple test would be to disconnect the stator plug by the TPS and using a meter on VDC , connect negative to ground and using positive check and see if you have any DC volts on the connector FROM the regulator, with key off and key on ( don't start bike). The results should be no volts DC.

Check some of the following posts, read through some of my posts, detail is in there someplace;